Denys Smith Memorial trip : the geology of Knaresborough Gorge : YGS 1st June 2008

This guide is dedicated to Dr Denys Smith, expert on the Permian rocks of Britain and Europe. The field excursion illustrates the Permian and Quaternary geology of Knaresborough Gorge. The Gorge is a marginal glacial feature cut at the edge of the Devensian Ice sheet during the last Ice-Age. The River Nidd has cut down through the Permian and Carboniferous sequence. The Permo-Carboniferous unconformity is exposed revealing a buried relief of low hills. The Permian Cadeby Formation dolomites above the unconformity show massive subaqueous dune bedding and traces of ooids indicative of formation in a Bahamas Banks environment. Tufa-rich spring activity on the west side of the gorge has resulted in the formation of a large tufa screen with a small cave behind where it has partly collapsed; this is Mother Shipton’s Cave.